1. Field of the Invention
The present invention relates to a prefabricated therapeutic prosthesis for below-knee amputees and to a set of such prostheses adapted to fit most below-knee amputees.
2. Brief Description of the Prior Art
After a below-knee amputation, the residuum swells with edema and then, as healing progresses, gradually shrinks over a period of time. Because the diameter of the residuum changes, a series of therapeutic prostheses must be provided until a definite prosthesis can be fitted. In addition to serving as a guard, a primary function of a therapeutic prosthesis is to apply pressure on the residuum, limiting the amount of fluids accumulating in the amputation site and reducing the amount of post-operative edema. Another important function is to promote weight-bearing ambulation.
The loss of a lower extremity by amputation has profound physical and psychological consequences. Early ambulation is extremely important to the physical and psychological rehabilitation of the amputee. In the past, therapeutic prostheses have been relatively narrow in the anterior/posterior dimension such that the popliteal area is compressed and the patient's weight carried on the patella. Pressure on the popliteal area interferes with blood circulation necessary for healing and pulling on the medial and lateral hamstrings flanking the area tends to spread open the incision as the patient puts weight on his or her amputated leg.
Many post-amputative patients are old and are so weak that they cannot walk on one leg with crutches or a walker. The supplemental support of a lightweight, temporary prosthesis, on which the patient can bear weight, can make a critical difference between ambulation or bed-chair confinement, with its attendant complications. In the past, therapeutic prostheses have been made based on a cast or on measurements taken from the patient, requiring the services of a skilled prosthesis. Because each therapeutic prosthesis must be custom-fitted to the individual patient, prosthesis design and fabrication has been quite expensive, which cost is likely to be a growing problem with increasing numbers of older citizens and emphasis on medical cost containment.